Focused, hands-on problems for sharpening your DevOps and server-side skills. Some teach specific concepts while others mirror real-world scenarios. Every challenge includes hints, feedback, and automated solution checks.
A worker node dropped to NotReady and part of the workload went with it. The container runtime is fine and the control plane is healthy; the trail leads from kubectl symptoms down into systemd and the kubelet configuration. Diagnose the node and bring it back.
A Snake game Deployment and ClusterIP Service are already running in the snake namespace. Create a Traefik Ingress that serves the game over HTTPS using an existing cert-manager-issued TLS Secret.
A Deployment running a distroless Chainguard nginx image (cgr.dev/chainguard/nginx) is deployed in the namespace webapps, fronted by a ClusterIP Service. Port-forward that Service to localhost port 3333 on cplane-01, use curl to save the response body to /home/laborant/index.html, and verify the file is accessible and contains the expected content.
A Job manifest at /home/laborant/batch-job.yaml is exiting with a non-zero exit status. The Job has limited retries configured. Inspect the cluster and the manifest to find the bug, fix it, and reapply.
Create a multi-container Pod with different user IDs per container while sharing a common group ID at the Pod level for collaborative file access.
Use kubectl proxy to open a local, already authenticated HTTP endpoint to the Kubernetes API server, then use curl to list every Secret in the gliese-581 namespace and save the raw JSON response to /home/laborant/secret-list.json.
Update a production NGINX ConfigMap to restrict TLS to v1.3 only, then verify the change enforces the security policy.
A Deployment is using a disk-backed emptyDir volume. Convert it to a memory-backed tmpfs volume for better performance — but make sure to set a size limit to prevent the Pod from exhausting the node's RAM.
A distroless pod running in the cherry namespace has no shell or debugging tools. Use kubectl debug to attach an ephemeral container, test connectivity to the request-logger service, and verify the request was received in its logs.
A Deployment is stuck with Pods in ContainerCreating state because the required ConfigMap was not created. Fix the issue to make the application accessible.
